Category Archives for "Acoustics"

Just What Your Mix Needs – Surveillance Tower Reverb

surveillance tower reverb pluiginI know, I know. You can’t finish that mix until you get the sound of an old surveillance tower to pull it all together. But where to find one? Well you’re in luck as the impulse responses from the Teufelsberg National Security Agency tower in West Berlin are now available. Best of all – it’s a free VST plugin.

The Teufelsberg security tower is a three-domed structure erected on a “devil’s mountain” of WWII rubble dumped on top of a half-finished Nazi military school. From this perch high above Berlin, the US government and its allies listened in on the communists of the Eastern Bloc and Soviet Union. It’s still standing, and you can add its cavernous sound to your tracks, thanks to Balance Audio Tools.

The plugin provides 6 different IR reverb sounds, all with fast, zero-latency convolution. There are only two controls, blend and gain, along with A/B compare and preset saving functions. It’s available as a free plug-in for Mac, Windows, and even Linux, and it’s open source.

Download it here.

Have a listen to what it sounds like.

If you want to tour of the structure, check out the video below.

New Music Gear Monday: PSI Audio AVAA C20 Active Bass Absorber

PSI Audio AVAA-C20One of the problems with most studio control rooms or small home studios is that fact that there are problems in the low end response. We try to control these with bass traps, but to be effective, normal passive traps take up a lot of precious room. There is an alternative however, and that’s to use a new breed of low frequency absorption that’s active, and that’s exactly what the PSI Audio AVAA C20 Active Bass Absorber does.

The AVAA C20 works on frequencies from 15Hz to 150Hz and it’s dead easy to set up in that there are no settings or calibration, only an on/off switch. So how does it work?

When audio sound waves hit a wall they build up pressure, which makes them bounce back into the room, reinforcing some frequencies and attenuating others, which creates an uneven frequency response. A normal passive bass trap takes that pressure wave and turns it into heat with material like fiberglass or rockwool, but you need a lot of it to be effective, especially at lower frequencies. The AVAA C20 has a microphone that measures the pressure of the sound wave. An acoustic membrane then is driven to absorb the volume of air going through the acoustic resistance of the front panel of the unit, turning the pressure of the sound wave to zero so it doesn’t bounce back into the room.

The interesting thing is that the AVAA C20 is totally analog and there’s no DSP involved. No, it’s doesn’t make a sound either, but it does the job of a bass trap up to 20 times as large as the unit!

The PSI Audio AVAA C20 is not a small investment at $2000 each, and you’ll need 2 for a 400 square foot room (one for each corner). Unlike physical passive traps though, these are easily portable, so you’re buying something that you can use in any environment for a long time. Check out the video below or go to the website for more info.